Chapter 4 · verse 13 · gita.yoga.org

Bhagavad Gita 4.13

चातुर्वर्ण्यं मया सृष्टं गुणकर्मविभागशः। तस्य कर्तारमपि मां विद्ध्यकर्तारमव्ययम्

The fourfold caste has been created by Me according to the differentiation of Guna and Karma; though I am the author of it, know Me as non-doer and immutable.